CNN just made a major change to its debate rules that will benefit one of the GOP's most surging candidates

Republican presidential candidate Carly Fiorina speaks at the RedState Gathering, Friday, Aug. 7, 2015, in Atlanta.
AP Photo/David Goldman
CNN is changing the rules for its Republican debate later this month, likely opening the door for one candidate to qualify for the main stage: former Hewlett Packard CEO Carly Fiorina.

The network announced the change on Tuesday after more than a week of pressure from the Fiorina campaign. Many analysts and pollsters also criticized the debate criteria for unfairly keeping Fiorina off the stage despite the fact that she has been surging, both in national polls and in surveys of key early states.

The network originally released rules in May. Those rules said it would average the results of qualifying polls conducted between July 16 and September 10. The top 10 candidates would then be invited to the main debate, while candidates who earned at least 1% in an average of three national polls would get a spot in a second, lower-tier debate.

Critics pointed out that because only three national polls have been conducted after the first debate, CNN's criteria was unfairly glossing over voters' opinions after the August 6 debates on Fox News. Fiorina experienced a post-debate poll bump following a strong performance at the August 6 "happy-hour" debate.

CNN now says that it will now take two criteria into account: both the rules in May, as well as any candidate who averaged in the top 10 in polling between August 7 and September 10.

The new rules virtually guarantee that there will be at least 11 candidates on the stage.

Fiorina's campaign immediately applauded the decision.

The Republican National Committee, which is co-sponsoring the debate and had taken flack from Fiorina's team as well as high-profile conservative pundits, also said it supported the decision.

At least one of Fiorina's Republican rivals, retired neurosurgeon Ben Carson, also cheered the news, saying Fiorina had proven "her viability and standing and deserves the same platform as the rest of the candidates."

Previously, a spokeswoman for CNN had said that changing the rules was not possible because it would be a violation of FEC guidelines.

"CNN published the criteria for the CNN-Reagan Library debate on May 20th. It will encompass polling data from three weeks prior to the first debate and five weeks following," CNN spokeswoman Barbara Levin told POLITICO last week. "Federal Election Commission guidelines make it clear that these criteria cannot be changed after they have been published. We believe that our approach is a fair and effective way to deal with the highest number of candidates we have ever encountered."